318 REPORT — 1851. 



any case it would involve the associated labour of several persons for many 

 years to produce. But the number of instances now catalogued is so large, 

 and the mode of collection and arrangement such, that I believe science 

 would derive no very material or proportionate advantage from the bestowal 

 of much more time and labour to increase it. 



The hase of induction now produced embraces between 5000 and 6000 

 separate eai'thquakes, and as this is the main use of an extended catalogue, 

 if that number be deemed sufficient, the object is answered, although some or 

 even many recorded earthquakes within our period had remained unadded to 

 the list. That some might be so added I doubt not. It is possible that many 

 trustworthy records of these events exist in Russia, as respects the north-west 

 of North America and Northern Asia. In Central and Northern India such 

 may also be found ; while there is little doubt that in the ancient libraries of 

 the Levantine monasteries, and in those of Spain and Portugal, a rich mine 

 of such information remains yet unexplored, to which we had no access. 

 For other portions of the inhabited earth's surface, records are almost or 

 altogether wanting. Of these the most important and interesting are, Mada- 

 gascar, and the interior, indeed the whole, of Africa including Abyssinia, 

 except its northern coast and the Cape of Good Hope, Greenland and La- 

 brador, Northern and Eastern Asia, Northern Australia, and the Pacific 

 Islands generally. 



The constructors of former catalogues have usually been at no pains to 

 make any systematic arrangement of their materials ; each is a mere chronicle 

 of events, in partial sequence of date, but otherwise mixed with such disre- 

 gard of order or relative importance, that reference to any special class of 

 phaenomena, except by exhausting it from the mass by reading it all through, 

 was impossible. 



The succeeding catalogue aims at a tabular arrangement, in which the 

 more important elements of earthquake facts are placed in separate columns 

 for each instance, and thus reference facilitated. The catalogue is divided 

 into six columns, embracing — 



1. The date and time, as nearly as recorded. 



2. The locality or place of occurrence. 



3. The direction, duration, and number of shocks in each case, so far as 

 these are recorded. 



4. Phaenomena connected with the sea ; great sea or other waves, tides, &c. 



5. Phenomena belonging to the land ; meteorological phaenomena pre- 

 ceding and succeeding, and all secondary phaenomena. This embraces all 

 those minor although occasionally important facts, that are mixed in earth- 

 quake narratives with the principal facts, which we might call the " elements 

 of the earthquake," as here comprised in our first three columns. 



6. The authority for the record. 



Many of the dates in the earliest periods of the catalogue and up to about 

 A.D. 1000, are extremely doubtful ; on collating separate authorities for the 

 same earthquake, even at much later periods, and in cases of occurrences 

 the most remarkable, and one would suppose well known, the discrepancies 

 that are found are marvellous. 



The dates of the eighteenth century have not been attempted to be altered 

 to new or old style, but in each case, as far as possible, the style (old or new) 

 as mentioned by the original author is given ; very many of the dates are 

 given however by narrators of this period without any intimation of whether 

 they refer to old or new style. 



The time of day is not often given in a reliable form. In times and cquq-. 



